The present invention is generally directed to an apparatus and processes for treating, such as by coating substrates, and more specifically, to a coating apparatus including a coating die with one or more laser position sensors and which coating die enables coating processes that deliver precise coating layer thicknesses and widths to, for example, cylindrical, sheet, or web substrates. The resulting precision coated substrates provide articles or devices that are useful in, for example, printing systems and printing processes such as organic film coated drum photoconductors, thermal fusing rolls, and the like useful articles. The apparatus and coating processes of the present invention can be adapted to provide value-added and enhanced performance capabilities to known printing and copying devices, such as printers, copiers, facsimile, and related multifunction printing devices.
In embodiments of the present invention can be readily adaptable to the manufacture of precision coated articles, such as, photoreceptor rolls and drums, fuser rolls, backer rolls, cleaning rolls, specialty coated papers or transparency stock, photoreceptor web stock, coated paper web stock, and the like articles or materials.
In embodiments, the coating processes of the present invention provide valuable benefits and excellent satisfaction levels in the manufacturer of coated articles and apparatus or devices incorporating the coated articles, for example, in providing coater articles with uniform coating thicknesses and homogenous coating layers, in avoiding materials waste or reducing manufacturing cycle times and costs, and in downtime and productivity losses associated less efficient coating methods and apparatuses. These and other advantages of the present invention are achievable.
There remains a need for reducing defects resembling brush marks along each edge of the deposited coating. These brush marks can remain as defects in the dried coating and can ultimately print out as undesirable artifacts in the final electrophotographic copy.
In a typical electrostatographic printing system, a light image or digital image of an original to be reproduced is recorded in the form of an electrostatic latent image upon a photosensitive member such as an organic photoconductor and the latent image is subsequently rendered visible by the application of electroscopic thermoplastic resin particles which are commonly referred to as toner. The visible toner image is then in a loose powdered form and can be easily disturbed or destroyed. The toner image is usually fixed or fused, for example with a thermal or radiant fuser roll, upon a support which may be the photosensitive member itself or another support sheet such as plain paper. Other related marking technologies are known, for example, liquid immersion development, and solid or liquid ink jet imaging technologies wherein a liquid, solid, molten, sublimed, and the like marking formulations are deposited onto an imaging member, imaging intermediate member, or image receiver.
In the dip coating process, a cylindrical drum is dipped into a tank of coating material and then withdrawn, with a portion of the coating material adhering to the drum. The adhered coating material is then allowed to cure.
In the slot die coating process, coating material is caused to flow through a slot while a photoreceptor belt of a width approximately equal to the length of the slot is fed past the slot in a direction transverse to the length of the slot.